Whatever fits, well that used to be my approach however with this illustrated book, you can nail down exactly what you need -
http://www.moparrmotorconsulting.com/ If it had torque specs, it would be a freaking assembly guide and it's well worth the money although it's cost me a lot of time scrounging to find just the right fasteners!
Here's an example
Hinge to door bolts 3/8"-16 x 1.36" Lg. hex head SEMS bolts with paint cutter and pilot point. Phosphate finish (prior to paint) grade 5. (quantity 12) washer 3/4", length below washer 1.36", washer thickness .11" head height .20" Chrysler part number 6026531
Hinge to pillar quantity 14, 3/8" x 1.12" Lg. hex head SEMS bolts with paint cutter and pilot point. Phosphate finish (prior to paint) grade 5. Washer is 1.12" and .13" thick. The two uppers (part number 6029744 but all measurements the same as the other 12 with part number 6028064) have sealer on the trheads and threads into the upper hinges from inside of the vehicle.
This book has more detail than you want and that's what makes it a great reference for all those fasteners you were unsure about. The book does body, chasis, drivetrain, frame and more.